4-{[4-({[4-(2,2,2-Trifluoroethoxy)-1,2-benzisoxazol-3-yl]oxy}methyl)piperidin-1-yl]methyl}-tetrahydro-2H-pyran-4-carboxylic acid is disclosed in PL1 as a 5-HT4 receptor agonist, which is useful in the treatment or alleviation of disease conditions mediated by 5-HT4 receptor activity; in particular 5-HT4 receptor antagonistic activity, such as gastroesophageal reflux disease (GERD), gastrointestinal disease, gastric motility disorder, non-ulcer dyspepsia, functional dyspepsia (FD), irritable bowel syndrome (IBS), constipation, dyspepsia, esophagitis, gastroesophageal disease, gastritis, nausea, central nervous system disease, Alzheimer's disease, cognitive disorder, emesis, migraine, neurological disease, pain, cardiovascular disorders, cardiac failure, heart arrhythmia, diabetes, and apnea syndrome (See NPL 1 to 13 and PL 2 to 7).
Simply an white solid has been produced in the previously known methods of preparing 4-{[4-({[4-(2,2,2-trifluoroethoxy)-1,2-benzisoxazol-3-yl]oxy}methyl)piperidin-1-yl]methyl}-tetrahydro-2H-pyran-4-carboxylic acid, described in PL 1. Therefore, neither a crystal nor mixture of crystal forms have been known to the public.